Plant maintenance is common in process industries due to unplanned failure of control system components and devices. Maintenance departments plan preventive maintenance of all critical system components and devices in order to prevent such unplanned plant maintenance but preventive maintenance does not guarantee complete elimination of spurious trips.
Traditionally preventive maintenance is scheduled based on calendar time or run time. Research suggests that only eighteen percent of assets have an age-related failure pattern, while eighty two percent exhibit a random pattern. This data shows that preventive maintenance provides a benefit for only eighteen percent of assets, while missing the other eighty two percent possibly resulting in failures.